The present invention relates generally to arming systems, and particularly to safing and arming systems using explosive trains.
In existing weapons, such as bombs, or the like, a potential exists for an inadvertent arming thereof in the event the weapon is mishandled prior to use. These weapons often employ out-of-line safety mechanisms powered by explosive charges as a means for preventing the inadvertent arming of the weapon due to such mishandling. Such out-of-line safety mechanisms often include an explosive chain in which one link thereof is located out of the chain thereby interrupting the chain in a weapon-safe condition, and then is moved into the chain to establish a weapon-armed condition.
To be effective, any weapon safing and arming mechanism should be secure enough to completely ensure that a weapon remains safe when necessary. Yet to be totally safe and effective in use, such a mechanism should not assume an arming configuration until the last possible instant. That is, the safing and arming mechanism should be stable and secure in a safing condition, yet be able to move into an arming condition as rapidly and as precisely as possible so arming a weapon will be reliable and can be delayed until the most desirable instant.
In the past, arming and safing mechanisms such as disclosed in Report AFATL-TR-79-80 have been designed to solve these apparently conflicting requirements by mounting the explosive chain movable link on a slider which is securely held in the weapon safing condition and is freed by an explosive charge which breaks the slider in tension or collapses it under compression. However, in these mechanisms, because the slider is simply overpowered to be released, the slider is freed and moved into a weapon arming position by the same forces which, in effect, cross-couple those slider freeing and moving forces.
The above-discussed conflicting requirements of security and stability in a safing configuration yet rapid and precise movement into a weapon arming configuration presents many problems for mechanisms in which the slider disengaging and moving forces are cross-coupled. In such cross-coupled mechanisms, the unlocking force must be large enough to overpower a slider which, itself, must be quite strong in order to insure safety, thereby exposing an unlocked slider to moving forces which may be far larger than necessary or desirable for moving the slider into a weapon arming condition. Therefore, using the same forces to both unlock a slider which is securely held in a safe condition, and move that slider into an arming configuration may make the mechanism difficult to control with precision.